The present invention relates to a shaped concrete block and in particular an interlocking concrete block used for the construction of a retaining wall.
Retaining walls are necessary to secure soil embankments adjacent roadways, rail lines, parking areas, etc. from sliding or giving way as a result of loading, underground pressures, weathering due to rain and other shifts in terrain. A retaining wall must withstand horizontal pressures from the retained soil behind the wall which could cause the wall to give way.
Traditionally, such walls have been constructed from concrete, bricks, wood ties and other similar materials piled or erected to form a wall behind which earth is back filled. With the ability to mold and cast concrete blocks rather inexpensively, improved retaining walls have been designed by stacking concrete blocks.
One known type of concrete block is provided with a hole which allows a pin to be driven through it into corresponding holes in the blocks of the underlying courses. In addition to the significant on-site labor requiring careful alignment of the blocks, the pins afford limited vertical stability, resulting in a wall having reduced strength. Grids have been used in conjunction with the blocks to add strength to such walls. These grids are placed over the pins, between the blocks, and laid out into the back fill. However, the grids offer little additional strength as the pins shear the grids over time causing the grid material to fail.
In my co-pending application Ser. No. 08/820,443, filed Mar. 12, 1997, now U.S. Pat. No. 5,951,210, an improved pinless, mortarless, interlocking block is shown. However, the need still exists for an interlocking block which can withstand a great horizontal force from behind the wall.
Furthermore, due to the significant weight of concrete blocks, a need exists for a block which can be lifted more easily, and placed in position without pinching the installer's fingers.
It is an object of the present invention to provide an interlocking concrete block for constructing retaining walls which can withstand a great horizontal force acting from behind the wall.
It is a further object of the present invention to provide a concrete block which is easier to handle such that the block can be lifted more easily and placed in position without pinching the installer's fingers.
It is a further object of the present invention to provide a concrete block which can be stacked securely in a variety of configurations.